To run a Windows Aero troubleshooter

Your computer's display consists of two pieces of hardware: a video card (also known as a graphics card or display adapter), which is installed inside your computer, and the video monitor, where you see all the text and graphics your programs display. Windows uses drivers to work with these hardware devices. The majority of display problems are caused by incorrect, corrupted, or missing video drivers. Hardware failure or incorrect installation make up another set of problems, and external factors can also cause video problems.

If you have just installed Windows, or have changed your video card and are experiencing problems, the most likely cause is a missing or incorrect video driver. Most video cards will come with a disk that contains drivers and other software. Before you install it, check the information that came with the video card to be sure it supports your current version of Windows. If not, go to the manufacturer's website and download the most current driver for your version of Windows. For more information on drivers, see What is a driver?

There are two basic types of monitors: CRT (cathode ray tube) monitors and LCD (liquid crystal display) monitors. Both types produce sharp images, but LCD monitors have the advantage of being much thinner and lighter. CRT monitors are larger, heavier, require more desk space, and produce more heat than LCD models.

If you need to update the Windows device driver for your monitor, you'll need to know the brand and model, which is usually printed on a label on the back or bottom of the monitor.

When Windows is installed, it attempts to identify the hardware it is installed on. By default, if it doesn't recognize the video card in your computer, Windows will install a generic video driver. This generic driver usually does not provide the same level of support as a driver written specifically for the video card. To fix this problem, you need to install the correct driver for your video card. Go to your video card manufacturer's website to download a driver. You'll need to know the make and model of your video card. For more information on installing drivers, see Update a driver for hardware that isn't working properly.

CRT monitors are often more prone to outside interference than LCD monitors. Interference can be caused by devices that transmit radio frequencies (RF) (such as a baby monitor or CB radio), or devices that produce magnetic fields (such as a motor in an electric fan), or even by just having a tangle of power cables on or near the monitor.

Radio signals can interfere with the signal going between your computer and monitor, and in some cases can cause horizontal lines to appear, as well as other interference. To reduce interference, move the RF device away from the computer, or move the computer and monitor away from the device.

Moving magnetic fields (such as from an electric motor) can cause flickering when near a CRT screen. A static magnetic field, such as from your computer's speakers, can cause color shifts or incorrect colors in the area near the magnet. This color shift is caused by parts of the screen becoming magnetized. Occasionally the color shift will remain after you remove the source of magnetism. To help reduce or eliminate the color shift, you can use the degaussing option on most monitors. Most newer monitors automatically degauss when you turn them on, while older monitors might require you do to it manually. Most monitors have a button or menu option that enables you to degauss it manually. Degaussing a monitor will de-magnetize the inside of the monitor, removing the color shift. Unfortunately, if the monitor is exposed to the source of magnetism for too long, degaussing will not be able to clear it up, requiring you to repair or replace the monitor.

DirectX is a Windows technology that includes video, animation, and sound features, which help your computer get more performance out of multimedia programs such as games and movies. The DirectX Diagnostic Tool is designed to help you troubleshoot DirectX-related issues.
This tool can give you information about your system, such as memory and processor speed, as well as the installed version of DirectX, and whether it is operating correctly. For more information on DirectX, see DirectX: frequently asked questions. To use the DirectX Diagnostic Tool, see Run DirectX Diagnostic Tool.

Most video monitors have a specific range of resolution they can display. If you specify a value outside that range, it can cause the monitor to display incorrectly, or not at all. Normally when you change resolution, Windows will wait a short time for you to confirm that you want to keep the resolution. If you don't confirm, Windows will change the resolution back to its previous value. However, if you accidently confirm it, but the monitor cannot display the new resolution, you will need to restart Windows in Safe Mode and reset the resolution to one that can be displayed by the monitor. For more information, see Change screen resolution.

Using two or more monitors on your computer can enhance your experience with using video games, spreadsheets, image-editing programs, or anything else that benefits from a larger screen size. For more information on installing additional monitors, search Help and Support for "multiple monitors."

Windows Vista uses the new, more stable Windows Display Driver Model (WDDM), which does not allow you to use more than one video driver when you use multiple monitors on a computer. Errors usually occur when you have more than one video card from different manufacturers, including any video support built into the motherboard on your computer.

To use multi-monitor support with more than one video card, all the cards must use the same driver. This usually means using the same video card, or different cards from the same manufacturer (provided that they use the same driver). Most new video cards enable you to set up two monitors using the single video card, so you don't have to use more than one card for two monitors. For more information on using your video card, go to the manufacturer's website. For more information on using multiple monitors, search Help and Support for "multiple monitors."